Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Power PC G4: Busted fan and other issues

B

blueapple612

macrumors newbie
Original poster
Jul 5, 2010
13
0
MN
I have a Power PC G4 that I am trying to get rid of but wanted to wipe the hard drive first. After turning it on I heard bad sounds from the fan region. Sure enough, the fan blade is cracked. I also spotted something that doesn't look right though I have no idea what it is or what happened, and I fear heat may have been the culprit (images B and C.)

So, 2 questions:

1- Where might I find a replacement fan?
2- Is there something wrong with that black wire (terminates in white plug) that seems to connect to nothing, and the melted brown scab peeling away from the rest of the board below it? (See B and C.)

PowerPCG4Problems.jpg


Specs:

Power Mac G4 (digital audio)
Mac OS X Version 10.4.11

Processor:
Dual 800 MHz PowerPC G4
2 MB L3 cache per processor

Memory:
1.25 GB SDRAM​


Thanks in advance for any help.

-Adam
 
I had one of those 38mm thick Silenx fans in my G4 DA and it was very loud because it was too tight a fit at the back.
I replaced it with one of these, matching the position of the heat sensor to the original. It has worked well for 2 years and it moves more air than the original fan.
Also, a dual 800MHz processor would make your Mac a Quicksilver unless its processor was upgraded.
 
Last edited:
Justinz and Dave H,
Thanks for your replies and fan information. I will look into replacing it.

Dave H,
I wasn't aware of the "Quicksilver" designation, but that is the machine I believe I have. Is it still considered a Power PC, or did I refer to it incorrectly somehow?

Do either of you suspect there is an issue with the apparently unconnected cable (images B & C) and the crispy-camera-film-looking material peeling away from the board?

Thanks again,

-Adam
 
blueapple612 said:
I wasn't aware of the "Quicksilver" designation, but that is the machine I believe I have. Is it still considered a Power PC, or did I refer to it incorrectly somehow?
Click to expand...

It's still a PowerPC.
Quicksilver G4s are just slightly newer than Digital Audio G4s and have a few differences.
The cooling scheme is one of them. Quicksilver G4s use the main (120mm) case fan for exhaust, and have a small intake fan at the back next to the power supply.
In Digital Audio G4s the main fan is for intake, and the power supply fan is used for exhaust.
Some Quicksilver owners have flipped the main fan around for intake, others have not. YMMV.
 
Last edited:
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148a Safari/6533.18.5)

Dave H,
Thanks for the clarification.

Are you able to tell if I should be concerned about the other issue shown in images B and C? I don't want to replace the fan and sell the device without knowing if that is a problem as well.
 
blueapple612 said:
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148a Safari/6533.18.5)

Dave H,
Thanks for the clarification.

Are you able to tell if I should be concerned about the other issue shown in images B and C? I don't want to replace the fan and sell the device without knowing if that is a problem as well.
Click to expand...

no, the brown stuff is just a pice of tape and that wire looks as if it is to connect to the dialup modem (which probably isn't installed)
 
max¥¥ said:
no, the brown stuff is just a pice of tape and that wire looks as if it is to connect to the dialup modem (which probably isn't installed)
Click to expand...

Thanks,
I will replace the fan and sell the device with a clear conscience then. Thanks to all for your responses.
 
@ Dave H:
I purchased the Akasa fan you linked to, and have the whole thing apart and ready to install. The fan I bough appears to be 3-pin whereas the one I'm replacing was a 2-pin. Also, the old fan's connection had visible pins, whereas the new fan't connection seems to be female.

Do I need a female 3-pin to male 2-pin adapter for this thing?
 
@ Dave H:
I purchased the Akasa fan you linked to, and have the whole thing apart and ready to install. The fan I bough appears to be 3-pin whereas the one I'm replacing was a 2-pin. Also, the old fan's connection had visible pins, whereas the new fan't connection seems to be female.
Click to expand...

The yellow wire is an RPM sensor, and does not need to be connected on a QS.

For the power connection, I ended up using the fan's molex (hard drive type) power connector instead of the Mac's original one.
 
SilenX are great fans. I used to buy them a lot before I discovered the Antec Tricool series with dual ball bearings. Around the same cost but blow more air and last much longer than most fans. The 38mm thick is too fat for any G4 other than the MDD though. You would have been better off getting a 25mm thick model. My 120mm Antec is only 25mm thick and blows a very respectable 79 CFM.

When replacing the old system fan you might as well replace the power supply fan as well. At least open the PSU up and clean it. I have done this to a few G4 towers and never shocked myself. Just don't touch any of the capacitors and also leave it unplugged the night before you do it. Also you should press the power button after it's unplugged to discharge any current left.

Many people overlook the PSU fan but it's just as important. My Sawtooth has an Antec 80mm DBB in the PSU that blows 34 CFM. Being a tricool model it has a short cable with a 3 speed switch that I have sticking out of the PSU touching against the top inside of the case. The system fan has the same switch but rests directly under the optical/zip shelf.

When it comes to quiet fans though I would say Noctua is the clear winner. Their 120mm's onl;y blow around 50-55 CFM at max.
 
Last edited:
<see included photo>

So I should use the adapter (D) that came with the fan, but where (B or C) should I connect it then?
 

Attachments

  • QuicksilverInterior.jpg
    QuicksilverInterior.jpg
    199.7 KB · Views: 120
Alright, new fan is installed and connected.

I closed the case, reconnected power, monitor and speakers and fired it up. Everything boots up fine, but I couldn't hear the fan at all. This concerned me because previously I could hear the old cracked fan blade hitting the cage right after hitting power. I thought I may have a very quiet fan, but I opened the box and the fan wasn't turning.

How should I check to see if the fan is working? How long do I have to run a diagnostic before I cook everything in there from over heating?

Thanks again for your assistance and patience.

-Adam
 
blueapple612 said:
Alright, new fan is installed and connected.

I closed the case, reconnected power, monitor and speakers and fired it up. Everything boots up fine, but I couldn't hear the fan at all. This concerned me because previously I could hear the old cracked fan blade hitting the cage right after hitting power. I thought I may have a very quiet fan, but I opened the box and the fan wasn't turning.

How should I check to see if the fan is working? How long do I have to run a diagnostic before I cook everything in there from over heating?

Thanks again for your assistance and patience.

-Adam
Click to expand...

I just checked my fan and it starts up as soon as I press the power button.
Check the connections and try the other power cable if necessary.
 
Dave H said:
I just checked my fan and it starts up as soon as I press the power button.
Check the connections and try the other power cable if necessary.
Click to expand...

The connections seemed fine, but I plugged it into the other spot to see if that made any difference.

I powered it up, and still didn't hear the fan. I open the case and took a look, and the fan blade jitters every so often, looking like it's getting power but doesn't know what to do. A video of this is available here:

http://www.blueapplestudio.com/misc/Fan.MOV


I'm guessing it isn't working right. I'm going to do some more research, but if anyone is familiar with this behavior off the top of their head I'd be thrilled to know a solution.

Thanks.
 
I've done some reading and saw this post:

http://www.neowin.net/forum/topic/614113-cpu-fan-wont-spin-new-build/

They (collectively) suggest checking to see if the fan spins freely with your finger. Mine does. Other things suggested to check are:

-fan dead
-pins on motherboard for your fan are broken (or badly connected)
-the wires in the fan are badly connected

I think the pins are fine, though I am no expert, and the connections are as tight as I can get them to go. If I had a dead fan would it even do the intermittent stutter turn that it's doing?

I replaced a 12V fan with a 12V fan of the same dimensions with (what appears to be) an adequate CFM rating. I am at a loss at this point.

Should I just duct tape a can of compressed air and an egg timer together and remind myself to manually spray this thing every so often?
 

Attachments

  • fans.jpg
    fans.jpg
    638.4 KB · Views: 112
Try connecting either of the molex power cables to your hard drive.
If it works, then the problem is narrowed down to the fan.

If you bought it from the link I gave, here is the contact info from their website.
Toll Free Office Line: 1.877.243.8266
Local Office Line: 1.585.218.0120
24 Hour Fax Line: 1.585.218.0125
Monday through Friday from 10AM - 6PM
Saturday from 11AM to 4PM.

The old fan in the picture is 86.5 CFM.
 
Last edited:
Dave H said:
Try connecting either of the molex power cables to your hard drive.
If it works, then the problem is narrowed down to the fan.
Click to expand...

The first place I tried connecting the fan was through the connection labeled "D" in an above post. These lines run directly from my hard drive, so does that already suggest it is a fan problem?

Dave H said:
If you bought it from the link I gave, here is the contact info from their website.
Toll Free Office Line: 1.877.243.8266
Local Office Line: 1.585.218.0120
24 Hour Fax Line: 1.585.218.0125
Monday through Friday from 10AM - 6PM
Saturday from 11AM to 4PM.
Click to expand...

I may give them a holler

Dave H said:
The old fan in the picture is 86.5 CFM.
Click to expand...
The new fan has an adequate rating though, right? I assumed that since the new fan states 35.49 - 105.44 CFM that I'd be safe. Though I'm beginning to feel like someone that did some reading on a Wikipedia biology page and assumed they'd understand appendix removal.

I appreciate your continued assistance in this.

-Adam
 
blueapple612 said:
The first place I tried connecting the fan was through the connection labeled "D" in an above post. These lines run directly from my hard drive, so does that already suggest it is a fan problem?
Click to expand...

If the exact same power connector works with your hard drive, but not the fan, then the fan is bad.


The new fan has an adequate rating though, right? I assumed that since the new fan states 35.49 - 105.44 CFM that I'd be safe.
Click to expand...

The fan rating means it starts at 35.49 CFM and moves more air as the the temperature rises, up to 105.44 CFM.
The old fan has a built-in heat sensor too and works the same way, but it tops out at 86.5 CFM.

Like I said in a previous post, I have the same new fan (and it replaced the same old fan) in my G4. It has run very well for two years, and that's with a hot-running processor upgrade and a hot-running video card upgrade.

One other thing, frozencpu.com has never answered their email for me, so the phone would be the way to go. They made a mistake in my favor once, and never answered my emails about it.
 
Last edited:
Got it sorted.

A wise friend of mine saw that the adapter that came with the new fan wasn't permitting adequate voltage to travel through, so he did some splicing. Fan runs like a charm now.

Thank you, Dave, and everyone else for your help.

-Adam
 
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back